When setting up a VPN on a SonicWALL, the option to have the Destination network obtains IP addresses using DHCP through this VPN Tunnel is missing. This is because you need to configure DHCP of VPN (VPN -> DHCP over VPN -> Select “Central Gateway” -> Configure, then tick the option to “Send DHCP requests to the server addresses listed below” and add the IP of your DHCP server), then you need to create the VPN.

At this point the option to have the Destination network obtains IP addresses using DHCP through this VPN Tunnel will still be missing, but once you’ve created the VPN, you can then edit it and the option will then appear under “Network”.